MATLAB-SIMULINK-based simulation for digital differential relay protection of power transformer for educational purpose



Differential protection was already applied toward the end of the 19th century and was one of the first protection systems ever used. Faults are detected by comparison of the currents flowing into and out of the protected plant item. As a result of the fast tripping with absolute selectivity, it is suited as main protection of all important items of plant. The article presents an approach to teaching relay laboratory using specially designed exercises that can be done using MATLAB-SIMULINK. This article presents a MATLAB-SIMULINK-based technology to simulate differential relay for determining behavior of it during transformer internal fault protection. The results show that this simulation method can work properly and this design can be used for power system simulation in MATLAB-SIMULINK. Evaluation of the simulation with more than 60 students is very positive in terms of their developing confidence in and understanding of this kind of relay operation. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 475–483, 2013